MedImmune, Inc. v. Genentech, Inc., 549 U.S. 118 (2007), was a decision by the Supreme Court of the United States involving patent law.

[1] It arose from a lawsuit filed by MedImmune which challenged one of the Cabilly patents issued to Genentech.

The case related indirectly to past debate over whether the US should change to a first to file patent system - in 2011, President Obama signed the Leahy-Smith America Invents Act, which shifted the United States to a first-inventor-to-file patent system.

[2] MedImmune was a licensee of the later Cabilly patent, but argued that the term had been improperly extended and that it need not continue to pay royalties past the original expiry date in March 2006.

GlaxoSmithKline and Human Genome Sciences both are challenging the patent under antitrust law (1).